U.S. House Committee on Homeland Security evaluates threat landscape 25 Years Post-9/11

Twenty-five years on from September 11, 2001, the United States House Committee on Homeland Security has published a review, “25th Anniversary Report: National Security Improvements and the Domestic Threat Landscape 25 Years After 9/11/01.” Led by Committee Chairman Andrew R. Garbarino, the document tracks the transformation of national security over the past quarter-century and outlines more than 20 strategic and legislative proposals to confront emerging hazards.

The findings illustrate how asymmetric risks have evolved beyond traditional, centrally coordinated plots into a diffuse spectrum dominated by self-directed lone actors, ideologically diverse violent extremism, and the weaponisation of emerging technologies such as artificial intelligence and unmanned systems. Crucially for the counter-terrorism medicine community, the report sounds renewed alarms around critical infrastructure vulnerabilities and non-conventional hazards, urging sustained investment in biodefense analysis, field biodetection capabilities, and broader chemical, biological, radiological, and nuclear (CBRN) preparedness.

For European medical responders and disaster planners, these findings reinforce that contemporary threat mitigation requires health systems to move beyond reactive mass-casualty triage. Strengthening biosecurity surveillance, cross-sector intelligence sharing, and specialised pre-hospital clinical training remains essential to maintaining operational resilience against low-probability, high-consequence incidents on both sides of the Atlantic.

The full findings and legislative recommendations are available directly via the U.S. House Committee on Homeland Security.